Re: [sfc] Progression of use case documents in the SFC WG

[[e-mail]]

Hi, Med,

  I'm not sure if the aims of BBF are the same as IETF's. 
For a developing technology, I'd think use cases might be discussed
where the technology is developing.
  In some way, I don;t think that is not duplicative work.

Thanks,
Wei
 


"sfc" <[e-mail]>  2014-03-28 15:44:10:

> Hi Jérome,
> 
> I fully agree there is no need to duplicate work. 
> 
> If there is already text/document in the BBF side, wouldn’t be 
> efficient to cite those document rather than editing another with 
> the IETF stamp?
> 
> Cheers,
> Med
> 
> De : sfc [mailto:[e-mail]] De la part de Jerome Moisand
> Envoyé : jeudi 27 mars 2014 13:55
> À : [e-mail]
> Objet : Re: [sfc] Progression of use case documents in the SFC WG
> 
> Agreed with the chairs proposal. 
> 
> There is no point duplicating work performed by other std bodies, it
> is much better to use it as a an input, while letting specialized 
> discussions occur between groups of corresponding specialists. BBF 
> leverages IETF work all the time, well, it’s time to have IETF 
> leverage BBF work.
> 
> Being co-editor of the BBF work, I’ll make sure that new use cases 
> identified by BBF will be communicated in a reasonably timely 
> fashion to IETF. We do have a few new ones in the works. And we’ll 
> work with the authors of draft-meng-sfc-broadband-usecases to 
> consolidate with BBF work.
> 
> Tx
> Jerome
> 
> Side note: draft-meng-sfc-broadband-usecases seems to cover two topics:
> 1.       a basic form of service chaining (‘BNAS’ –I guess this 
> means BRAS/BNG- to CGNAT) which is already covered by BBF use cases
> 2.       then a lot of material about IP v4/v6 transition matters 
> (DS-Lite, MAP, etc), which doesn’t seem to have a direct 
> relationship with service chaining per se. Anyhoo, it turns out that
> there is another BBF work item in this respect, so corresponding 
> material should find its rightful place.
> 
> 
> From: sfc [mailto:[e-mail]] On Behalf Of Ken Gray (kegray)
> Sent: Thursday, March 27, 2014 8:28 AM
> To: [e-mail]; Jim Guichard (jguichar); [e-mail]
> Subject: Re: [sfc] Progression of use case documents in the SFC WG
> 
> I'd give a +1 to the chairs …
> 
> If there is going to be more than one document (and we seemed hell 
> bent on more than one at the BoF … we could, as a group, settle on 
> "a small number"), that they have some focus. 
> 
> I don't find the focus or organization described by the chairs 
> onerous - in fact, GIVEN that we have the liaison(s) in place and 
> that they do want a voice here, and that at least one of them has a 
> "domain focus" I find it logical to start with broadband and develop
> use cases in a set of non-trivial domains. 
> 
> They had to define "a small number" …or "a small number" becomes a 
> big number.  Now we know how many "a small number" is.
> 
> If draft–liu is stripped of enough content by the categorization of 
> the "small number" it's efficacy should be questioned.  To your 
> specific point, as a group we can decide on moving the specific text
> you mention back to Problem or otherwise re-home it.  It shouldn't 
> be the sole reason draft-liu exists.
> 
> I would have gone a bit further than the chairs, frankly. 
> 
> There is SO much use case literature out there right now, I frankly 
> don't want to see the IETF repeat any more than it has to.  I would 
> hazard that most of us have read these things before in one of several 
forums.
> 
> So, IMO, the use cases should provide support for the problem 
> statement and the development of a proposed header functionality 
> (solution), and as such should illustrate significantly unique 
> requirements …so that we can assess the efficacy of the proposed 
> solutions.  I hope the "owner by area" described by the chairs will 
> take on the responsibility of making sure that their examples are 
> significantly unique for  consideration and addressable in the solution. 
 
> 
> Because their work represents the work of many (whole organizations)
> and is hopefully further distilled by the author here into unique 
> examples, in fairness their contributions should probably be 
> credited to "various" with a nod to their organization.
> 
> And, because these use cases have been reviewed in other forums by 
> many people, the process should be more expeditious.
> 
> 
> 
> 
> From: "[e-mail]" <[e-mail]>
> Date: Thursday, March 27, 2014 3:07 AM
> To: "Jim Guichard (jguichar)" <[e-mail]>, "[e-mail]" <
> [e-mail]>
> Subject: Re: [sfc] Progression of use case documents in the SFC WG
> 
> Dear chairs,
> 
> Some comments below:
> ·         The proposed actions are not aligned with the feedback 
> received in this thread (Progression of use case documents within 
> the SFC working group). Answers to that poll are in favor of having 
> a generic use case document. IMHo, it is not fair to ignore what was
> voiced for by wg members in the mailing list as part of a formal 
> call with clear questions. 
> ·         Some of the text that was adopted by the WG as part of the
> Problem Statement (use case as part of the Problem statement) has 
> been moved to the generic use case. That text is governed by this 
> charter text: “1. Problem Statement: This document will provide a 
> summary of the
> problem space to be addressed by the SFC working group including
> example high-level use cases. Additionally, the working group will
> normalize nomenclature and definitions for service function chaining.
> ”. What to do for that text? 
> ·         Having the generic use case document and some few detailed
> ones do not conflict. It is only a matter of scoping.
> 
> Given what is stated above, I disagree with your proposal. 
> 
> If I have to choose (again), I would vote for having one single use 
> cases document. Having one single document will help focusing on 
> core aspects and would simplify the wg activity: review, last calls, 
etc.
> 
> Cheers,
> Med
> 
> De : sfc [mailto:[e-mail]] De la part de Jim Guichard 
(jguichar)
> Envoyé : mercredi 26 mars 2014 18:54
> À : [e-mail]
> Objet : [sfc] Progression of use case documents in the SFC WG
> 
> WG:
> 
> In a message back in January, we (the chairs) proposed that the SFC 
> WG handle the topic of use case documents as follows:
> 
> 1) Have the WG develop one use case document that documents a small 
> number of representative use cases.  The document presented by 
> Hongyu Li at the Vancouver BOF could serve for this purpose
> (http://datatracker.ietf.org/doc/draft-liu-service-chaining-use-cases).
> 
> 3) For additional use cases not covered in 1) above, allow for a 
> small number of documents that are applicable to specific
> environments (e.g.  mobility, data center, broadband, and so forth.)
> These documents would provide more detailed information and 
> applicability of SFC to these specific environments, and would need 
> to go beyond what is covered in the general use case document (1). 
> Note that it is not the intention to have every potential use case 
documented.
> 
> Since then, and based on the presentations/discussion in London, it 
> appears that we have a number of documents that warrant being 
> developed as standalone documents. Specifically:
> 
> 1) A use case document on mobility, e.g., http://datatracker.ietf.
> org/doc/draft-haeffner-sfc-use-case-mobility/
> 
> 2) A use case document on Data Centers, e.g., http://datatracker.
> ietf.org/doc/draft-kumar-sfc-dc-use-cases/
> 
> 3) Possibly a use case document on Broadband scenarios. However, use
> cases from a broadband perspective are being developed in the BBF 
> (see the liaison statement at https://datatracker.ietf.org/liaison/1304/
> ). We also have http://datatracker.ietf.org/doc/draft-meng-sfc-
> broadband-usecases/.  It does not seem appropriate to adopt a WG 
> document on the topic of broadband (at least at this time) without 
> clarifying the relationship between draft-meng-sfc-broadband-
> usecases and the BBF work. In addition, we would need to understand 
> why two efforts — one in BBF and one in the IETF -- on the same 
> topic would be appropriate. Hence, at the present time, we do not 
> intend to adopt a WG document on broadband scenarios, and expect to 
> receive primary guidance on this topic from the BBF.
> 
> That leaves: http://datatracker.ietf.org/doc/draft-liu-sfc-use-cases/
> , a more general document. But that document includes text on three 
> topics that would be covered in more detail elsewhere (broadband, 
> mobile, and DC). While this document could contain pointers to the 
> other documents, that leaves the document with very little 
> standalone content -- raising the question of what should be done 
> with it, or what content it could incorporate in order to be 
> worthwhile as a standalone document.
> 
> Thus, the chairs recommendation at this time is:
> 
> 1) Call for WG adoption of draft-haeffner-sfc-use-case-mobility-00.
> txt and draft-kumar-sfc-dc-use-cases-00.txt as WG documents (target:
> informational).
> 
> 2) Defer action on draft-liu-service-chaining-use-cases  and draft-
> meng-sfc-broadband-usecases per the above discussion.
> 
> Does this make sense?
> 
> Jim & Thomas_______________________________________________
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